Crude petroleum has traditionally been used as a primary source for raw materials for producing numerous specialty chemicals. Particular specialty chemicals that can be produced from the petrochemical raw materials include fatty alcohols. Fatty alcohols have many industrial and commercial uses. For example, fatty alcohols act as surfactants which are useful in personal care and household products, such as detergents. Fatty alcohols are also used in waxes, lubricating oils, cosmetics and solvents. However, obtaining fatty alcohols from crude petroleum requires a significant amount of energy and involves the use of a non-renewable energy source.
Further, even those fatty alcohols that are obtained from renewable sources, such as from plant or animal derived fatty acids, generally are prepared using a hydrogenation step. Hydrogenation is a costly process step but is utilized to eliminate the double bonds of unsaturated fatty acids. A number of prior art references disclose genetically engineered microorganisms that produce products including fatty acid derivatives such as fatty acid esters and fatty alcohols. For example, reference is made to International application publications WO 2007/136762; WO 2008/119082; WO2010/075483; WO2011/008535; and WO 2011/019858; and U.S. Pat. No. 6,143,538. However a need still exists in the field for improved fatty alcohol production from bioengineered microorganisms that is efficient and cost effective and further that is tailored for use in particular industrial applications. In certain industrial applications, the presence of one or more double bonds in a fatty alcohol is not a desirable characteristic because the double bond lowers the melting point, reduces the shelf-life and reduces the heat stability of the fatty alcohol. Therefore, compositions and methods that provide products having increased saturation levels in fatty alcohols are also commercially beneficial. In addition, it would be beneficial to optimize specific blends of fatty alcohols (e.g., blends of predominantly C12 and C14 fatty alcohol carbon chain lengths) to target particular industrial applications that utilize these fatty alcohols or derivatives thereof.